BC cancelled their spring game this year, and maybe they had the right idea. This isn't a big deal for many people here, but it's another step backwards in terms of getting the "buzz" for casual fans. It's also really poor PR to wait until the week prior to tell people what you are doing instead of being up front from the beginning. It wasn't a last minute decision not to have a "scrimmage".
If it's just going to be a practice, then really go all out to make it like FanFest with more activities for kids during the practice, special raffles to those in attendance, and more opportunities to meet other sports.