Without wanting to rebuke you too strongly, I think it's worth mentioning that you're addressing a forum whose active membership represents thousands of years of collective experience in the music business. Perhaps a theme across a number of posts in this thread is that whoever is telling you "how the business works" may be misinformed themselves, or experienced with only a tiny corner of the business.
What you've experienced so far is not how the business works, but how the pay-to-play business works. You pay for a small gig, and if you do good, then you get to pay for a larger gig.
Why are folks so skeptical? I think it's because most working musicians have never played a ticket-selling gig. For this reason, it's not credible that ticket-selling is a necessary or even beneficial step towards developing a musician or a band.
Personally, I'm of two minds about variations on the pay-to-play theme, such as ticket-selling. On the one hand, ticket-selling seems to figure into some of the most outrageous horror stories experienced by emerging bands. On the other hand, people do pay money for the enjoyment of playing music, for instance by buying instruments or taking lessons. I gladly pay for my kids to participate in music groups that perform. I have no fundamental objection to selling time slots in showcase gigs. But you may need to decide in advance how much money you want to sink into it.
You've gotten a lot of harsh responses. I don't think it's your fault. It's just that the subject matter itself is controversial. For this reason, I hope that you still feel welcome at TB, and that you will stick around and keep us posted on how things go!