Hi there
Interesting question and something i've wondered myself

Ive had similar experiences with textiles/clothing carpets wallpaper etc. My understanding is that when there is an incresed sense of awareness within a dream the 'material' component of the dream itsself is penetrated, its almost like being on the threshhold of becoming lucid. Our dreams have substance, though the substance differs from that of our physical plane. During sleep our consciousness in varying degrees awakens and operates on the astral plane. This astral substance has a different quality, feel, texture to what we are used too on the physical level.
However when our awareness increases about any ONE thing that we are dreaming about then its almost as if we are penetrating that particular aspect of our consciousness. Maybe by becoming aware of the 'substance' that your garments/clothing is made up of in the dream is another way of imparting the idea that you are understanding the deeper levels/layers of for example your persona or attitude 'clothing' what it is composed of or made up from, Its fabric if you like.
In my view as well art work can be a beautiful stimulus for accessing depths of emotion. Artwork and colour particularly, resonate with different levels of consciousness. Art can not only inspire us and move us in ways which are profound but can evoke various emotions and feelings within that may have been locked up. This way of gently opening the heart can be stimulated in our dreams (a healing dream) often through symbols and divinely inspired colours etc which can if you like be looked at as a direct manifestation of the higher feminine/masculine energy - Love, compassion and Wisdom.
Just some more food for thought

Malakeli