(Ibid. 4) "even the tenth generation shall not come": If it is written "for all time," why need it be written "the tenth generation"? It is mufneh (free for interpretation) for purposes of comparison and identity (gezeirah shavah), viz.: It is written here (in respect to Amoni and Moavi) "the tenth generation," and there (in respect to mamzer) "the tenth generation." Just as here, "for all time," so, there, for all time.
(Devarim 23:5) "Because they did not greet you with bread and with water": Not only because of this, but also because of the counsel (of hiring Bilaam against you [Ibid.]), viz. (Michah 6:5) "My people, hear now, what Balak king of Moav counseled, etc."