I know everyone hates subscriptions, and it sucks how much friction is being put in the way of folks who don't want it. But I've loved having an HP Smart plan. Most of the time I don't print a ton so I pay $1.50/month for the random items that come up in my life. Then every August I bump up the plan since my wife is a teacher and prints a lot more in preparation for the school year. I've gotten 3 ink refills which would cost ~$210, vs ~$90 for the subscription in the past 3.5 years and I never had the annoying moment of needing to print something but being low on cyan and having to run to Staples.
Don't get me wrong, they are likely doing the same thing that many other subscriptions do. Hoping you sign up and you forget that you have it and they just bring in the money.
But if you know you are going to use it (like maybe you already take a regular trip to a printer), you know how much you are going to print, it isnt horrible.
Sure being locked in for 2 years sucks, but given they are sending you hardware some sort of contract is likely required.