There were a couple of reasons.
In-state cost of attendance in CA is higher than out-of-state here in MD, and it's easy to get in-state tuition after a year. I actually didn't apply to any CA schools. My grades were low, but I had a very high PCAT. CA schools are more interested in GPA, so I had no real shot at in-state schools.
Maryland was my top choice though (tied with Minnesota where I was waitlisted). I was impressed with the students at interview day, and I liked the dual-degree options. There are lots of opportunities to get involved in research at all levels. In fact I'm working in a pharmaceutics lab that does interesting translational work. We do experiments in the lab and in the clinic.
Additionally, since I'm still not sure what I'm going to do after pharmacy school, I am working hard to keep my options open for residency and/or fellowship. Many of these programs value work experience, and there are lots of opportunities to work as a student at Johns Hopkins (or other places) on the weekends. I think it's pretty easy to find student intern positions here in Baltimore.
I don't know which other school you're looking at, but make sure that the school has everything you want out of a pharmacy school if you're going to take out loans. If the school doesn't have the tools to allow you to succeed and you can't get into the field you want in pharmacy, it seems like a waste of time and money. But if the other school has everything you need to get to where you want, go with the cheaper option.
I highly recommend you look at your loan payment plan after school. This may make or break your decision. Don't forget, your loans will accrue interest during residency or fellowship, if you go that route!