I'll address the latter part first. I would be setting up a GMail, Hotmail, etc for myself and letting all of the retailers know of the switch. Mixing personal and professional is never a good idea. I have a couple of different emails so I can use one particularly if it is an apparent spammer situation. My "legacy" email I've had for decades now with Comcast gets jammed with spam...you are fortunate to only have Cabela's and Bass Pro inundating your inbox. Try shopping with a couple of dozen purveyors of guns and equipment and toss in Amazon for the icing. I regularly have to delete a couple of hundred emails per day....of the laptop and the phone as they coming bombing in on both.
Merry Christmas to you and yours in the auld country. My prayers are with the UK that 2020 will be the year that you folks reflect the will of the people and sever those ties with the EU who would love to control every last aspect of your law, finances and culture.