Virgin internet because they do that thing of putting your bill up all the time until you complain about it, which means a lot of older customers or people lacking confidence get shafted. A horrible business model (and not the only company doing this). That and Branson trying to devour the NHS.
Not keen on Tesco historically because they used to abuse the planning system horribly, building on playing fields against local wishes etc (and appealing to central Government to overrule local planners)
Currys/Carphone Warehouse/Warburtons bread for donating to the Tories amongst other crimes. A shame most of their current donors are shady hedge funds that are unboycottable unless you’re some high net ‘worth‘ type.
Three for being awful if you want to leave their network (had no reception at work so reasonable), so hard to leave at the end of a contract, really condescending, passing you around departments to people who’d claim ‘we have solutions for you’. No you don’t, just let me sign off and leave it rather than waste my time, they said the same the previous year and nothing changed. Then a runabout to get a PAC off them.
Also never do McDonalds, but that’s a decades old boycott for rainforest stuff etc.
I use Apple stuff because I had an HTC android phone via a contract about a decade ago and it would barely work at all. At least with Apple you know there is a kind of minimum standard so things will work (although my first iPad didn’t really have enough memory to run properly after a few iOS upgrades). Plus I generally buy second hand or get hand-me-downs so price isn’t really an issue.