A Bikes at Work trailer is likely the way to go for two large dogs, but as you've noticed, not cheap.
The Wike cargo trailer is significantly cheaper (I own one), and could potentially hold one of the dogs at a time as it's rated for 125#. It may be too small for your crate, and regardless, that would only be one dog.
Hauling a large dog is one thing that I cannot do without a vehicle - I have a "small" Newf who is only around 130 lbs. Food is easy, though. Chewy.com has pretty much every food imaginable (including quality large-breed specific kinds) and delivers for free with minimum purchase.