Though the increase is only 5% this year (on top of the 13% rise last year plus the yet to be announced annual rise for next year) the cc surcharge will increase to 25% in the coming years, some of the worry may be that the precedent will be set so further increases in the surcharge level may continue.
Whilst many cc boaters will use the facilities more, this is not always the case. For example, if boater A travels 10 miles each week, using 10 locks that is only 500 miles and 500 locks a year, many summer boaters do much more than that every year Also most are probably, out of necessity, more frugal with water and rubbish. The other main point raised is that by charging a small percentage of boaters (who often are the least able to pay) a large increase raises less money than charging everyone a small increase. The licence dodgers and continuous moorers are my biggest bugbear, mainly because they often hog the best spots.
Removing non payers would make people feel better but not raise any money and I have to admit I have no solution as to how this could be done easily.