Your photographs are your work and they are your asset. If you work as a professional photographer they are your only asset. Copyright is your title to that asset.

Make no mistake, the reason others want your work is so that it benefits them. For non-commercial use this may be acceptable, you may choose to donate your work to support charities or other causes you approve of. But it is difficult to imagine why anyone would give away their work to commercial entities whose only real interest is using your work to make money for themselves. If you license your work for a fair fee, it benefits you as well. But if you assign copyright or give a free license, you must be one of those rare people who hand out wads of money in the street to strangers who are sometimes better off than you are. Who, by the way, would not think about supplying you with free goods and services just for a credit.

If you really have no interest in money and think charging for use of your work is somehow vulgar or distasteful, ask for it anyway and then donate to your favourite charity.

Please remember that even if you do not care about copyright, others do. If you allow free use of your work it undermines every other photographer who wants or needs to retain their rights. It sends a message to clients that photographs are valueless and photographers are gullible. The law reforms that gave authors control of their own work were hard won, and are an ongoing battle to maintain; commercial publishers would like nothing better than to be able to use photographs without payment or permission, as their constant lobbying for free use of 'orphan works' demonstrates. Moreover they commonly disregard assertions of the moral right to be identified as the author.

Another major issue is that of control of how the image may be used. If you do not restrict use, you have little practical influence on whether your work may be used in ways you consider objectionable.

Finally, also bear in mind that photographs can change in significance and value unpredictably with the passing years. What may seem of little interest today may be special and far from commonplace someday.  Whose photographs are they anyway? Yours, so keep it that way.