Question: Undeniably, graciousness differs from money! Graciousness is a behaviour and quality, whilst money is a physical a medium of exchange, a unit of account, and a store of value.

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> [gratuity (n.)](https://www.etymonline.com/word/gratuity#etymonline_v_11931 "Origin and meaning of gratuity")
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> 1520s, "graciousness," from French *gratuité* (14c.) or directly from Medieval Latin *gratuitatem* (nominative *gratuitas*) "free gift," probably from Latin *gratuitus* "done without pay, spontaneous, voluntary," from *gratus* "pleasing, agreeable," from *gratia* "favor" (from suffixed form of PIE root *\*gwere-* (2) "to favor"). Meaning "money given for favor or services" is first attested 1530s.
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Answer: 
It can be surprising because usually, you see the more common construct with an adjective and a noun both plural, and it can be counter-intuitive (or 'uncomfortable') even for native speakers.  

But this is the way to go, as *curieuses* qualifies both *une estime* et *une amitié* and as this nominal group is plural (there are 2 elements), the adjective must be plural.

If we replace *une estime et une amitié* with *sentiments*, it sounds more familiar: *Roland avait pour lui des sentiments curieux*.
It is indeed both correct and weird for native speakers. It's even weirder when an adjective qualifies two nouns from a different genre, a masculine and a feminine:

*Julie porte un T-shirt et une jupe neufs.*

Here the adjective "neuf" has to be at the masculine form because in grammar masculine always wins, but it sounds very weird when it comes right after the feminine noun!

So generally we will try to change the word order to *Julie porte une jupe et un T-shirt neufs.* to make it sound a bit better...

Many natives would make the mistake to write *Julie porte un T-shirt et une jupe neuves.* They considered changing the rule, but it hasn't changed so far.