I know that they need to balance the books, but some crude maths, based on an average increase of £10 for 10k tickets (kids prices frozen), then it's only an additional £100k of revenue. So you'd only need 250 fans (at an average ticket price of £400) to decide not to renew to actually be worse off than price freezing. Then there's the lost match day revenue.
Very crude maths I know, but it will be marginal the benefit to the financials from doing it.