I'm not implying that this was made on purpose -- vendor lock-in might happen "naturally" as well, when company becomes big enough that they can start unilatera

I'm not implying that this was made on purpose -- vendor lock-in might happen "naturally" as well, when company becomes big enough that they can start unilaterally change prices/conditions/services knowing that costumers will accept that (even grudgingly), because they have nowhere else to go or it is too expensive/complex. Google is the perfect example of this strategy. Smaller player or startup would probably go bankrupt very fast if acted with such disregard for their costumers.