I'm not quite sure what this is saying.  Does this mean that if you come in to Applebees without your pants, you can get a good deal on soup and salad?  Gee, they really are a friendly place.  Maybe it is their staff that is bottomless, just like a topless bar, but the reverse.  Or maybe they've removed the floor of the place and you walk on dirt.  I'll bet it saves money on carpet cleaning.

In truth, it would have made more sense to use all three lines on the sign and center it...

Bottomless

Soup and Salad

$5.99  M-F  11-3

But then again, that's probably giving them too much credit.