I think you need to find a compromise that works for you between size, weight, expense, and level of protection. There are some small and relatively light and portable UPS option available but to be honest, I never carry one, even though they are a great idea, think I need to start using one. You are operating a computer catered to sound production.
If you are on a big tour, sure, why not go with some expensive (and heavy) power conditioning. Otherwise, seems like overkill to me. Let insurance handle any replacements necessary if the venue manages to fry your equipment. Always bring a backup! Really comes down to your personal degree of risk tolerance and how expensive or irreplaceable your rig is.
I am usually more concerned about getting electrocuted by hinky power than I am about my equipment frying, although I don't want that happening either. At home/studio I have a UPS and power conditioner. For performances the PA is fully protected by a power conditioner but not in use for my modeler. I think it is always important at a minimum though to always plug in through some kind of surge protector. I also like using GFCI surge protectors as they provide additional fast-acting protection against shock hazards and are inexpensive, small, light, and easy to stuff into a backpack or gigbag side-pocket.