Can you charge a different application fee for a married couple versus 2 individuals?

[Kimberly T.]

I'm researching PMs in other markets we're considering buying in, and have seen some PM sites with info for prospective tenants. When I look at their apps, I have seen some with the following type of set up:

"Each adult must apply and pay a separate application fee" and then later in the app it says each applicant must submit the $50 app fee or $75 for a married couple.

So, if 2 unmarried adults wanted to apply, they'd have to pay a total of $100, but a married couple would only pay $75. Wouldn't this constitute discrimination based on marital status? Thoughts?