In that case it's plausibly a good deal, and of course it would be extremely deplorable to try to take away people's ability to buy pancake mix, or smoke, or drink Coke, or drink Everclear, or snort cocaine. People are almost always better at making the choices that are best for themselves than anyone else would be, because they both know more about themselves and care more.

But that doesn't mean they're necessarily good at it, and explaining how to get better at it is the opposite extreme from being condescending. Condescending is, "Oh, you wouldn't understand," not, "Here's an demonstration of how to work this out for your own situation, which you'll be able to understand," which is what my comment is.

Maybe you think it's condescending because everyone already works out hourly wages for thriftiness-directed activities, but I can assure you that your friends are very unusual if you think that.