> TBH, those vendors sound seriously sketchy absent some credible explanation for why they think they need to charge more for a wedding.

I mean, you can just ask why if you're curious. Most of them are sole proprietorships. It's not like you're dealing with a large corporation where pricing is set by a corporate office.

Re: bailing, honestly I think most of them just react negatively to being lied to because there's some element of a personal relationship involved in this kind of service. I'd similarly be pretty pissed if my boss lied to me intentionally about what I was working on.