Soaking is actually detrimental to pre-shed BP's. It strips away oils in their skin they need in order to properly shed.
Soaking, even at proper temperature is also stressful for BP's. I avoid it unless it's absolutely necessary, which is very rare (pretty much only if I find a BP with a repeat bad shed, which is rare). If I think a BP is dehydrated I just make sure the humidity is good and they have fresh water in their bowl, they know what to do from there
And if I find a BP that has crawled through it's waste I just give them a quick wipe down with a wet paper towel.
Now for the BP in the water bowl. On rare occasions some BP's randomly like to soak in their bowl, if they just do it once and not again it's fine, but if it's a everyday thing then there is a underlying problem. Like you said it could be just a lack of secure feeling spaces, or more likely it's mites. Their natural instinct with mites is to try to drown them. Either way I would definitely avoid buying any BP from that store.