I'm annoyed by this concept too, and am highly opinionated about it. I think what maybe I have a problem with is the negative connotation of the word 'addict'. Because, as a nurse, I see addicts as sick people, and people with habits or behavior patterns as well people. The term psychologically addicting is loaded, and infers something negative about a person, when really, they just have a bad habit that, when stopped, would be unpleasant, but not cause actual physical withdrawal symptoms.
I've worked psych and rehab and detox, and yes, psychological addiction is a thing, but we need to call it something else because it's just human nature. If someone is used to working out every day before work, and then they miss their workout one morning and just "aren't right" all day because of it, are they psychologically addicted to working out? Behaviorists may say no while addiction specialists may say yes. But there are people who take it to the extreme, and work out 2 or 3 times a day, and miss appointments and work and going out with friends so they can get 200 calories worth of cardio in- THAT'S when it's addiction and needs treatment.
Before we talk endorphins and such, let's take me as an example- I'm addicted to Mt Dew. Seriously. If I don't have one for 3 or 4 days, I am a total bitch. Yelling. Throwing shit. Then when I get my fix it's like a calm washes over me. I start smiling. No, it's not the caffeine and not the sugar I missed- I've tried stopping just Mt Dew and going ahead and subbing Coke, Pepsi, coffee, chocolate or what have you. I've accepted that I need a Mt Dew every other day or so. Am I psychologically addicted? Yeah. But I hate that term, because literally ANYTHING can be psychologically addicting, and because we're using the term "addicted" as a synonym for "bad", "harmful" and "destructive". Let's just call me a Mt Dew walrus like you suggest and leave it at that!