Perhaps if they employed a litte more comnjoined thought
I curently have two active UK sims (one for work and one for personal) and am about to supliment that with a German PAYG on a third mobile so that I can use the unlimited data bundles while in Europe. That will make one person with three active SIMs. (and three phones which will all be going, "Mamma, Mamma," come feeding time at the charger-zoo.)
If they need to cut down on these things, then the industry needs to become a little bit more intelligent with how they do things. I mean, with the market the way it is at the moment, what else do they expect?
(in case you're wondering, one is a works iPhone which doesn't do dual SIM, my personal preference is the Jolla and the third is an android that I'm using for SatNav ... so dual simming isn't realistic)