[dns-wg] request about RIPE vs. ISP and RFC 1921, 2.1

Hello,

if RIPE assigns an large ip net to an ISP - Does RIPE accept, that this 
ISP ignores RFC 1921, 2.1 [1] (for commercial interests)?

Are commercial interests a valid reason [2] for RIPE, that an ISP does 
not set (generic) PTR records for an used IP?

Does or does not RIPE claim the compliance with (basic) RFCs (like RFC 
1921, 2.1 - I think it is a basic, that every IP must have a correct PTR 
record.) for assigned IP nets?

I hope, I found the correct mailing list for my question. If this the 
wrong list, which should I use for my question?

Best regards,
thomas polnik.


[1]
2.1 Inconsistent, Missing, or Bad Data
    Every Internet-reachable host should have a name.  The consequences
    of this are becoming more and more obvious.  Many services available
    on the Internet will not talk to you if you aren't correctly
    registered in the DNS.
    Make sure your PTR and A records match. For every IP address, there
    should be a matching PTR record in the in-addr.arpa domain. [...]

[2]
RFC 2119
[...]
3. SHOULD   This word, or the adjective "RECOMMENDED", mean that there
    may exist valid reasons in particular circumstances to ignore a
    particular item, but the full implications must be understood and
    carefully weighed before choosing a different course.
[...]