Let's consider another type of sales person, maybe somebody working retail. They enter the showroom and see 10 different customers, each unattended. It's a diverse group by gender, age, ethnicity and quality of clothing ( representing socio economic level ). Who should they approach first and why ?
If I'm the business owner, I probably hope they approach the customer who is likely to spend the most based on past experience. That can be dangerous territory if the business consistently approaches older, well dressed customers and ignores the rest.
The only answer is to employ enough sales people so that every customer gets assistance quickly, reducing the perception of bias and maximizing sales.
Bringing this back to strip clubs, I don't mind if some strippers intentionally ignore me because of my age as long as several are willing to approach me. In fact, if those strippers are more comfortable with older customers, I may prefer that.