There might be a way to Chain it, if you spend feats on the MetaDevotional feats (which I have yet to implement), however that means you have both a Devotional (of which you ONLY get 20, and considering how they require lower level devotionals for the higher level ones, that means you have to branch out more than you might otherwise want to), AND a feat investment. So that's a LOT of resources the Priest is dumping into a trick to make them immune to environmental heat and cold. If he wants to do that, great. He should be able to be effective.
Create Food and Water is not a domain spell, so a Priest will never have access to it.
Remember, Priests only get access to domain spells from the deity they serve, and they MUST serve a deity, no priests of causes here.
If the Priest wishes to devote a significant portion of the nonrenewable resources available to him, then yea, he should be able to do that for his part. However, it will almost certainly limit his more powerful options, such as higher level devotionals.Presumably there are many groups who'd prefer not to deal with such things. However, even then, it might be better if those groups dealt with survival and healing through magic items or something comparable (ToME-style inscriptions, maybe?), which would help to ensure that nobody has to deal with survival, instead of only resolving the issue for casters.