Your point seems to be “if we didn’t allow ourselves a loophole to to terminate the deal, or to make a profit from you some other way, we couldn’t possibly afford a ‘lifetime deal’.”
Only with more winky-faces. 
My reply is: why offer lifetime deals then? Your post has excellent, honest explanations for why “lifetime deals” don’t make any sense. You’re basically admitting that this can’t possibly be a lifetime deal. So why pretend it is? Why not be honest and only provide monthly or yearly deals?
This is the whole argument against falsely selling “lifetime deals,” and just saying (as @jlw does) “well, it’s worth it even if it’s two years” doesn’t cut it. It may not even last two years, as I have found in the past.
If I buy a two-year contract, I have some rights if you try to cut and run in six months. If I buy a “lifetime deal,” and give you the right to unilaterally change the terms, then I have no say at all when you stop providing a service in six months.
For now I see no reason to stick with my pay-an-honest-amount-per-year Private Internet Access account, rather than something that has T&C’s to allow itself to cut me off, and who even explains (honestly) here in the comments why they have to be that way.
