You are correct that without a scholarship or advanced standing you cannot go on summer cruise. I don't think that not going on summer cruise is the end of the world. Advanced Standing students would only do their 1/C cruise anyway. The cruise between freshman and sophomore years is CORTRAMID where you would spend a week in each community - SWO, Subs, Aviation and Marines. That doesn't necessarily mean you are at sea... you could spend your cruise alongside a dock in some cases. You get some sense of what each one is about but you might already have your own idea of where you want to serve.
For Marine Options I don't think missing summer cruise is a bad thing at all. You already know you're going Marine so CORTRAMID is a bit pointless and I sometimes hear Mt. Warfare is not all it's cracked up to be. That leaves OCS after junior year but that one's not optional and if you're still in the program, you're going if you are not injured.
Being on a cruise can give you some idea of what it's all about, and even be a lot of fun, but it isn't necessary. People who commission after college do not go on cruises which proves my point. JMPO.