Try truning thumb.db caching off.
Thumbnail views will still work, as Windows 7 Explorer and above now actually stores its thumbnails in a local database for its own use.
Windows 7 apparently generates these files for compatibility with older software that may expect such files to exist in folders with, for example, photos in them.
Unless you're running such old software, you can just turn this off without consequences (except that your system won't be fooling with your photo files to make Thumbs.db files in the background).
Open the start screen, type gpedit.msc and hit Enter.
The Editor will open to the top-level Local Computer Policy, so you will have to expand the User Configuration item in the left-side pane of the Editor window.
Drill down through Administrative Templates, then Windows Components, and click on the File Explorer item.
Near the bottom of the list in the middle pane of the Editor window you will find the setting “Turn off the caching of thumbnails in hidden thumbs.db files” (NOT turn off caching of thumbnail pictures.)
To edit this policy setting, either double-click on the title of the policy or click the link titled “Edit Policy Setting” to the left of the setting list after you select the policy. It is interesting to note that below the Edit Policy Setting link it indicates that the requirement is "At least Windows Server 2003 operating systems or Windows XP Professional".
To change the policy, merely check the “Enabled” radio button and click OK
Close the Local Group Policy Editor and you will notice that all of those thumbs.db files have disappeared.