I think you should always return faulty records.
I had an LP for Christmas that had a fault whereby the label wasn't attached properly to the record and was bubbled up, almost coming off. We sent it back, only for the replacement to be warped and I mean warped! The most warped LP I've ever come across! We're still awaiting a replacement.
I have some sympathy for small independent dealers, but most of the time, a cursory look before items are packed (I always request that LPs in shrink wrap are opened and mailed with the vinyl and outer sleeve separate), would save a lot of these issues. I remember an album that I received through the post with a really badly damaged sleeve. The shop tried to protest that it got damaged in transit, but the point was that it was sandwiched between two other LPs, which were fine, so it must have been packed in a damaged state.
Apart from the fact that damaged goods should always be returned, the other point to remember is that when you sell second hand vinyl, buyers expect the LPs to be in near perfect condition, with no folds or rips to the sleeve, so why should we be expected to buy new LPs that dont meet this criteria?
Having said that, I do put up with LPs with minor warps; its down to you to judge if the LP you have is acceptable.