Soooo..... you're suspicious of him because he's... good? [...]
His condition, incidentally, eats one (1) magic item, and then he doesn't ask for any more, even as you find them... people really over-blow the whole "he'll take your things" angle.... it's super insignificant, all things considered.
One reason people might distrust Gale so much is because, since many of the other companions have a big scary evil secret, people expect Gale to have one too. SH worships Shar, Astarion is a vampire and will bite you and others to death if you let him, Wyll made a pact with a demon and there's something off about his hero reputation compared to his skills/personality, and Lae'zel...is refreshingly open about her thoughts of you and her desires actually. But she wants to bring you to Gith who will almost certainly kill and/or enslave you and she's brainwashed, so you still can't fully trust her words.
This combines with the fact that Larian said they were releasing the evil companions first, so an not-obviously-maniacally-laughing-Gale must be secretly evil.
As to the last point, does he really only ask for one? I'm out-of-date patch-wise at this point, but I thought I remembered him taking multiple..?
