Gnucash in Stretch has hard dependency on perl. Specifically:
perl:any, libfinance-quote-perl, libwww-perl, libhtml-tree-perl,
libhtml-tableextract-perl, libcrypt-ssleay-perl, libdate-manip-perl

After confirming with the gnucash developrs (on IRC channel #gnucash), I
would like to report this as bug.

Perl is not a requirement for gnucash, and is only needed for querying
remote finance services such as yahoo finance

I suggest to change depends to suggests

thank you