If your stance on the importance of a beacon when skiing B/C is that it is "unnecessary but necessary", you have much to learn, and I strongly, strongly suggest you educate yourself before you go on any of those smaller trips.
Beacons are always, 100% necessary out of bounds, no questions asked. I mean why wouldn't you?
I think people forget how dangerous mountains are, and how easily they can swallow you up, literally. Growing up skiing resorts and becoming a confident in your skills can cloud your understanding of how powerful the landscape is and the potential it has to kill you. In my experience, it has taken years to afford the gear and take the appropriate courses to allow me to begin travelling in the B/C, and I'm just scratching the surface. This is something I want to do for a long time, and getting a couple quick thrills for me is not a risk worth taking. This is why I have so much respect for guys like Sage and Hoji and Jeremy Jones. Those guys are real professionals, and have a real respect for the landscape.
/steps down off of soapbox.
Have fun out there, but do it right. Beacons are expensive because they are pieces of safety equipment built to incredibly high standards, not something you want to fail at a crucial moment. There are other reasons, but for me, that is reason enough.