Risks involved are known to everyone able to use his brain.
But "wise explanations" about risks should not appear almost every time someone complains or points at a particular case of photo stealing.
If they persist to appear - it seems their authors may have more or less hidden (or even more or less non-councious, non-intentional) will to persuade the author complaining about his copyright broken: "better get used to live with thefts or don't post your photos on the Web".
This is, in a way, in some sense a JUSTIFICATION or AFFIRMATION of someone's work stealing.
No, we cannot agree with that (that thefts will be ignored and left without reaction).
Therefore we communicate about instances of copyright breaching. It also goes in line with this website policy.
If you are not concerned that your photo may be used somewhere without permission, if you do not care - than OK. I do not oppose your attitude. These are your photos and this is YOUR decision whether to protect them (and how - by not posting them perhaps) or not, allow for redistribution and republication in commercial (or any at all) media, etc.
But if you see someone complaining about copyright breaching, pointing at some particular media that breaches copyright than please, refrain from "teaching" the author that he "should better get used to living with that (thefts) or stop posting photos on the Net".
The complaining person, whistleblower does the right thing:
he/she warns copyright sensitive photo authors about the particular media which (as he knows by his own experience or knowledge) breaches copyright.
If you do not care - than DO NOT CARE "to the end" and stop teaching everynoe what everyoe knows (that thefts in the Internet DO happen). Just ignore it. Do not lecture people AGAIN that "ship (on a stolen photograph) happens"...
If you are copyright issues sensitive - than this information from whistleblower is useful and appreciated.
Normal person able to distinguish between the good and bad will never accept photo thefts.
Not everyone is obliged to distribute his work on a "free for all" / creative commons / freeware basis EVEN if he likes / wishes to share (by making photos available for viewing) for whatever reason.
If you are ready to give your work free of charge to anyone (without even knowing that your work is used) than OK - it's your right and I do not interfere with it and I do not tell even my opinion (whether you should or not), because it is "your business" and your photographs.
And please, in turn, ignore "whistleblowing" posts instead of teaching us again and again that "thefts happen"... We all know that.