Nor should it. The census counts persons, not citizens.
If the census data is used for the allocation of members of the House of Representatives based on population, this means districts with a disproportionate number of illegal immigrants and other aliens would be disproportionately represented in the Congress (especially considering numbers anywhere from 12 to 40 million of illegals).
Whenther you consider that fewer Citizens would warrant a Representative in those districts so enumerated, or that it would take more citizens in districts without that number of aliens present, the effect is the same: some are more represented than others.
Similarly, the allocation of tax dollars based upon populations which are composed of people who are not citizens and who may well not pay any taxes at all is unfair to those districts which are primarily composed of Citizens who pay taxes.