Contrary to many other lounges, the lounge at IC Park Lane is often quite full, so basic economics suggest they can charge a higher price. Whether you receive value for money is another discussion.
Ironically the fact that it is full makes it less good value because it tends to be noisy and difficult to find a good space too.
I honestly think that for not much more than £110 you can get a similar amount of food and drink in the local vicinity and be more in control of your time and environment. Who wants to travel to hurry back to a lounge twice a day, just to "get value" rather than doing what you want?
It's not a bad lounge and has a nice view but even back when I used to do points stays rather than cash stays there and it was something like £60 for RA's I didn't think it was worthwhile and never paid for it.