I don't think you're alone as I was getting 1.5Mbps on ADSL and now get 37.5Mbps on fibre which is fabulous but I didn't need to go that fast, 10 or 20Mbps would have been transformational for me. However the cost in giving me fibre to do 10Mbps is likely the same (fibre, cabinet, power, install etc) as 40Mbps, so would I want to pay ~£10 a month to go from 1.5 to 10Mbps? not really.
I remember when we first had ADSL here I was paying £40 a month, for half a megabit, it was great, hell of a difference to the old dial up system. the only reason I updated to ADSL at the time was because I had a lodger and the extra speed between us was great, plus at the time no more limits and cut off time.
i know things have changed now and most people could not cope with dial up, but I do know a couple who is still on dial up, their choice.
We do need more speed, but not all of us need 40 megabits and yet because we are a distance away from the exchange we have to pay extra for fibre to get extra speed.
If I had 8megabits, I would not even consider fibre.
Don't get me wrong, I am lucky to get the speed I get, but that is only because I am on a decent network and got myself a router that got a third party firmware that allows me to knock the SNR right down and for most things it is fine.
the only problem I have is playing Hd content.
Desktop machine now powered by windows 7 pro 64bit , laptop by ubuntu
On ADSL24 using C&W network.