If they pay fines and penalties, where's the problem? The Immigration Reform Bill contained language to address that. But strident social conservatives shouted it down nonetheless.
Thus...President Bush's intended message.
The fines and penalties suggested were mostly for “the path to citizenship”. The most valuable commodity, legal residency, was given away for free.
As for the “fines” you refer to, it is more appropriate to say “sweet deal”. Compared to the amount of social services consumed by the average illegal, the “fines” involved were pitiful.
Any fine that is acceptable must reflect the actual direct and indirect costs to the american taxpayer for legalization. Plus a (real) fine of course.
A superior alternative to fines is mere employment verification, along with actual (gasp) immigration enforcement.