This is being done at CC every day, all day for the past god knows how many years and 99% of crews dont seem to have a problem with it.
We simply do not have the time to wait until after you have passed 4000ft to give you a climb. By this time it will be too late, and you will be in confliction with inbound downwind traffic.
All we need is some crews to come and sit on sector and all be become clear