I think Pork Chop raises a valid point albeit obliquely.
Regardless of whether the organization in question is a government or a religion, few laws are ever enforced to the letter when it comes to minutia.
For example, virtually all violations of the U.S. Postal code are felonies. When Joe Blow, of Joe Blow's Lawn Service prints up a bunch of advertisements and goes through the neighborhood sticking them in the mailslots and mailboxes of the homeowners, he has technically broken the law and committed a felony at each and every address. Mailboxes and mailslots are property of the US Postal service and may not be used for this purpose. Will Joe Blow go to jail for what he has done? Will he have to pay a big fine? Of course not. Unless he repeatedly and habitually ignores warnings to stop, the government frankly has bigger fish to fry --especially right now.
In a similar fashion, what they have written in the past notwithstanding, I really really doubt if the organization of JW's truly cares what you feed your pet. Take tropical fish for example. Sometimes it's openly labeled and sometimes not, but almost all tropical fish food contains blood. Does this prevent Witnesses young and old from keeping tropical fish? Do JW's who keep tropical fish face judicial inquiry? Of course not. The organization of JW's has bigger fish to fry (no pun intended) --especially right now.
Therefore, pragmatically speaking, I agree with Porkchop.
However I think drawing a distinction between knowingly allowing an animal under your jurisdiction to consume blood (e.g. Watching the family cat killing and eating birds in your front yard) verses actively providing an animal under your jurisdiction with food containing blood (e.g. Placing food containing blood in the cat dish yourself) is not only ludicrous, it is illustrative of the loophole mentality that the legislation of morals invariably produces.
Laws have loopholes, moral issues do not. In other words, If it is morally wrong to actively provide an animal with food containing blood, it is certainly morally wrong to passively allow them to consume food containing blood, especially if if it lies in your power to prevent it.
In a more serious situations, the JW's themselves would be among the first to recognize the lack of any moral distinction here. For example, since it is morally wrong to actively provide a minor with alcohol to consume, it is certainly morally wrong to passively allow them to consume alcohol that they have obtained on their own, especially if it lies in your power to prevent it. In a similar application of the same principle, most JW's know that they can actually become party to any wrongdoing in the congregation simply by passively turing a blind eye to it.
Therefore I believe Gumby. If you made an issue out of it this and confronted the JW organization either by phone or letter, I've no doubt they would have recited the party line rather than explicitly or implicitly contradicting what has been put in print, regardless of how stupid that may have been.