Let me assure you that you're in the vast minority if you add little or no salt at all to your home-made burger patties.
Still meat is very low sodium, it is weird to say plant based alternatives have less sodium since both have as much salt as you add since there is almost none naturally.
The GP is talking about health conscious folks
I was going to edit the comment with this but in Canada we have a company called Metro(grocer) and they often sell 4x fresh beef patties for ~$4 which is 1lb(454g) of ground beef and exactly nothing else.
It's good to eat sans salt on bbq with your desired (typically salty) toppings.
I know people salt the patty while cooking, but the topic at hand is Beyond and their patties.