Two threads posted on the same day on the Chowhound website (chowhound.com) pose the problems involved in accommodating varied tolerances to spicy food. In "Was This a Social Faux Pas?", the original poster (OP) writes about hosting a meal at his home for coworkers and their families, for which his Thai wife cooked a number of dishes. She prepared two versions of each dish, one at the spice level she would normally make it at, and a toned-down version for those who couldn't take the chilli heat.
One guest took this as a personal insult, claiming that the OP and his wife were pre-judging his tastes in food. He made a scene and stormed off, leading the OP to wonder if he had been unintentionally rude. Almost all the responses were in support of the OP, telling him that he and the wife were very kind to go to so much trouble to accommodate those who couldn't tolerate much spice.
In the second thread, "Overheard in Thai restaurant … embarrassing 'Yankees'", the original poster (OP2) writes about dining at a Thai restaurant "designed for the American trade" that states on the menu that the dishes are made according to guests' tastes, on a spice level ranging from one to five. He overhears a woman saying, "We're YANKEES, we don't eat spicey [sic] food." OP2 then claims, "It was the 'Yankees' who brought spices to the colonies." This time, most of the people responding were against OP2, saying that 1) it's very possible the woman was being self-deprecating but they wouldn't know because they can't read her mind; 2) that not all Thai dishes are inherently spicy, and that perhaps the woman was asking to be steered to those; 3) where did he get the idea that Yankees brought spices to the colonies?; and 4) if the restaurant was willing to modify the spice levels for customers, who is OP2 to complain?
For me, both threads are about hospitality. Like many who posted in the first thread, I thought it was very nice of OP and his wife to try to adjust the food for people who can't tolerate much spice; it was double the work to make two versions of the dishes, and to take that as being rude is looking for an insult where there is none. Was the OP's wife betraying her culture by lowering the spice level? Of course not; even among Thai people there's a varying tolerance for chilli. In the second thread, OP2 was taking offence on the behalf of the restaurant, when, in fact, it was the restaurant that offered - on the menu - to adjust the spice level.
As anyone who's ever eaten street food in Thailand knows, the cooks there will adjust the dishes to suit the tastes of the customers. I've waited in a long queue at a particularly popular somtam vendor in Bangkok, and watched as the cook pounded the shredded green papaya in the mortar with fish sauce, palm sugar, chillies and garlic, personalising it for each customer. Did they want more (or less) chillies or garlic? Should she add dried shrimp or tiny crabs? Extra lime juice? The efficient way to clear the queue would have been to make the somtam in a large batch and dole it out as needed, but the cook realised that not everyone has the same tastes. She wasn't adjusting the green papaya salad only for me - the sole East Asian foreigner in the line; she also did it for all the Thai customers. Did I feel condescended to? Of course not - it would have been boorish to take offence where none was meant.
When my husband and I entertain at home, if I'm not the one cooking dinner, we serve Thai food, because that's the cuisine our domestic helper specialises in. We compose the menu together, making sure that there are some mild dishes as well as spicy ones. She always asks if the guests can take spicy food and, if I don't know, I'll ask her to tone down the heat slightly. Are we being condescending to our guests? Of course not - we're trying to make sure that they're happy with - and can eat without discomfort - the food we serve them. Because in addition to wanting to enjoy their company, why else would we invite them?