I guess to each his/her own. You have to prioritze and make sure you will be able to handle your finances after your intake.
My membership dues were quite costly(even for Grad.),but we were told the break down of our money. This included such things as dues paid for x amount of years, x amount of chapter functions and assessements paid for in advance etc. etc.etc. I don't think that is a bad ideal for I don't have to worry about how I am going to come up with certain monies for x amount of years.(I also feel that this helps to keep sorors active with that chapter for that's where their money is)
Now if said monies due can't be justified then there is a problem. But one must let their heart and mind be their guide. Only you know what you can handle.