Where can I try mattresses without worry about someone bothering me to make a sale or affecting their metrics?

Hi, tl;dr is the title

Backstory: my king mattress is sinking in on an outer 1/4th of it but I only sleep on the opposite 1/4th of it usually (I like to sleep on the edge of the bed) leaving like the middle like 1/2 of it still useable, so I personally have no need to buy a new one. My gf is long distance but in the next few months, she might start staying with me a few nights a month and I'll need to get a new mattress if the 1/2 left of the bed doesn't work for her, so I decided to start looking at mattresses to see what I'd buy if I needed to buy one in the next few months.

I was curious how Purple was due to the marketing.

I went into one to try Purple and the guy was very nice and generally let me be, but then I wanted to try other higher-end models and the store didn't have them, so he directed me to another store that had a bunch. The person working the store was busy finalizing a sale so I could try as many as I wanted and was unbothered.

I tried a bunch and found I liked the highest-end model but wanted to try other brands after reading about them on this sub, so today I went into another mattress firm that had both tempur-pedic and purple (highest-end) and a bunch of others so that I could compare them.

I walked in and told the person working the store that I was just looking, hoping to be left alone. As I tried mattresses, he kept asking me things and just wouldn't let me be. Stuff like trying to take a mattress matcher test thing or if I'd like to fill out a credit card application. When he asked me when I was planning to buy, I told him a year just so that he'd get the picture that I'm not trying to buy anything and to please just let me be, to which he responded "oh that just messes up my conversion rate" to which I said "oh sorry."

From then on, he still kept trying to talk to me and the picture I got is that he wanted me out of his store. He asked me what I was doing in a mattress store if I wasn't planning to buy for a year, to which I said "oh, I'm just enjoying life." which was again another attempt to get him to just leave me be while I tried to see what I liked in the case I had to buy one soon.

At one point he came up to me and asked me something like if I had heard of this festival where they paint faces and drink margaritas to which I said "nope, never heard of it. I don't drink" and he said basically said "doing stuff like that is enjoying life, not going into a mattress store wasting commissioned sales people's times" at which point I decided "yeah, screw this guy. I'm out. Definitely not buying from him if I end up needing one."

At one point he called up an employee at another store to ask if I had been in there for some reason. It was incredibly bizarre and the entire visit left me incredibly uncomfortable.

I never asked him to help me. I just wanted to be left alone. Are most Mattress Firms like this? Is there a place where I can try tempur-pedic and other mattress types without worrying about messing up someone's metrics or pissing someone off when they realize they can't pressure me into making a sale?