Also essential doesn't really mean their more in demand now than before in all industries. Mechanics for example are essential and still at work but cars if anything will be needing less maintenance now than before because so many people are out of work and not driving anywhere for vacations.

Additionally the places where there is simply an increased demand and need are a lot of 2 types of job 1) warehouse workers or 2) manufacturing. Warehouse workers don't have that strong of a bargaining position because places like Amazon are already used to constant turnover, surge by up to 200k a year already, and only really need warm relatively able bodied people of which there are loads right now that'd love a job. Manufacturing people are in a slightly better position as it's harder to just throw bodies at it but factories have limited ability to ramp up. Grocery store workers are kind of (1) employees where it's very easy to replace workers so it's tough for ununioned employees to demand hazard pay or raises because it's very easy to find replacements, especially so now when there's so many other service industry jobs that are out of work right now.

Having money is a feedback loop. You can't negotiate if you're skint.

With 22 million out of work, it's easily to replace an "essential" meat packer. It's far harder to replace an engineer or doctor even if they aren't essential

That's why white collar workers make so much money in the first place...