A couple of PPs have pointed out that the provision of meat analogs (veg burgers, dogs, sausages, etc.) is not really necessary as long as there are plenty of other things vegetarians or vegans can eat, some of which contain protein sources (beans, etc.) Omnivores see meat as a centerpiece dish and want to swap out one for one. Failure to make that swap makes a meal feel incomplete to them. Vegetarian cooking just doesn't work that way; main dishes tend to be mixed dishes, like soups or stews or casseroles or stir fries. There is a reason for this, besides the wonderful plethora of naturally vegetarian dishes available.
Meat analogs are just not that good. They are overpowering at best and icky at worst. I do not want to eat a meat analog dog all by itself in a bun, with appropriate condiments. It is too much. Maybe an eighth of one, like a pickle spear. Once a year, if that. We use meat analogs occasionally, but prefer to use them in tiny amounts mostly to make omnivores comfortable -- chili just doesn't feel right to them without something that looks like meat in it, for example, even when they know it is not meat. Red sauce for pasta. Shepherd's pie. Like that. We do have a brand of veg burgers we like -- but they don't pretend they are trying to be meat, and we want burgers only a few times a year, anyway.
It is nice when a host makes an effort to provide veg food. We appreciate it, and we're happy to bring it, too. We like your company, but we get hungry. But a one to one swap is not really necessary. Why not ask the guests? I don't know a single veg who does not automatically offer to bring a veg entree when accepting any invitation. We really don't mind, and would like to work with you to make it a coordinated and delicious meal. ETA: that hog dog bar sounds great! You won't mind if I skip the veg dog or only take part of one, will you? Thanks!