Snow tires/steels no TPMS insurance risk?

Not sure; would hope not. Move to Canada, lol?

I suspect the main issue is not your insurance, just that he could be procecuted, if he installs them on your (TPMS equipped) car. If he's fine with mounting and handing them over to you, I'd jump on that. If you're not setup to easily do tire swaps yourself, it is a frustrating imposition, though.

Here's something:

Having winter tires installed just got more complicated

Does it not seem strange, that TPMS will discourage people from getting safe winter tires?

I think what it's gonna take is amendment to the TPMS rules: to say that manufacturers have to come up systems that are conducive to tire replacement or swapping.

 

Who are "They"? I doubt that an insurance company would care.

I could understand a tire company not wanting to install wheels/tires without TPMS since TPMS has been required on vehicles for about the past 10 years.

I'd return the steel wheels if you can and get a set of refurbished OEM 16" Prius wheels and get some eBay center caps for them:
aluminum-16x65-wheel-rim-69600


The 16" steel wheels I bought from Tire Rack to use with Blizzak WS70 tires are a PITA, don't fit well, require different lug nuts and the wheel covers that came with them break easily and don't fit well either. You didn't say what winter wheel/tire size you bought but I put 16" wheels/Bizzaks on our 2012 Prius v Five instead of 17".

TPMS sensors are pretty cheap. I bought an ATEQ Quickset handheld programming tool to program in TPMS ID's on our vehicles when I do the twice-per-year changeover. The Quickset is about $150 and is easy to use.

The Carista smartphone app can also be used to upload TPMS codes into vehicle ECU through a Bluetooth receiver/cable that attaches to the diagnostic port under the dash.

 

You can get aftermarket TPMS sensors for about $30 a piece and have your existing sensors cloned. This will allow the snow tires to directly replace your normal tires with no additional setup in the car ecu. You can then go back and forth at will. See my post #36 in this recent thread:
TPMS Reminder - Batteries don't last forever | Page 2 | PriusChat

 

What about a non-TPMS equipped donut spare? Sounds more like a liability issue for the installer rather than an insurance issue.

 

For the v I believe there's a Camry steel rim that's 100% compatible. I'm using a Corolla rim on our regular Prius. The hub openings are correct, and dealership had compatible lug nuts. The OEM lug nuts also have the correct seat at the end for these steel rims, but look odd with the washer (for OEM alloys).